Humans with traumatic brain injuries show place-learning deficits in computer-generated virtual space

Spatial learning and memory has been linked to the hippocampus and temporal lobes and though these areas are often damaged in traumatic brain injury ( TBI), spatial learning deficits after TBI have not received much attention. In the present study, a virtual environment was used to challenge people w ith TBI to solve a task comparable to the Morris water maze, which in turn has been shown to be highly sensitive to hippocampal and frontal lobe dysfu nction in laboratory animals. A regular computer monitor was used to presen t 12 participants with TBI and 12 age- and sex-matched comparison participa nts with a computer-generated, three-dimensional "virtual arena maze,'' con sisting of a large round arena within a very large square room. Participant s were required to learn the place of an invisible target on the floor of t he room based solely on distal cues on the walls of the room. Eight of the 12 participants with moderate to severe TBI showed substantial place-learni ng deficits in comparison to the uninjured participants. Performance in the virtual environment correlated with self-reported frequency of wayfinding problems in everyday life and with scores on a test of episodic memory, the Rivermead Behavioural Memory Task. These data confirm that deficits in spa tial learning and memory follow TBI, and suggest that the virtual arena maz e may provide a new method for objectively assessing them.